1. Field
Embodiments relate to a light emitting device and a light emitting device package including the same.
2. Background
Red, green and blue light emitting diodes (LEDs) capable of realizing high luminance and white light were developed, based on development of metal organic chemical vapor deposition and molecular beam growth of gallium nitride (GaN).
Such LEDs do not contain environmentally harmful materials such as mercury (Hg) used in conventional lighting apparatuses such as incandescent lamps or fluorescent lamps and thus advantageously have superior eco-friendliness, long lifespan and low power consumption, thus being used as alternatives of conventional light sources. The key factors in competitiveness of such LEDs are to realize high luminance, based on chips with high efficiency and high power and packaging technologies.
In order to realize high luminance, an increase in light extraction efficiency is important. A variety of methods using flip-chip structures, surface texturing, patterned sapphire substrates (PSSs), photonic crystal techniques, anti-reflective layer structures and the like are being researched in order to increase light extraction efficiency.
In general, a light emitting device includes a light emitting structure disposed on a substrate, wherein the light emitting structure includes a first conductive type semiconductor layer, an active layer and a second conductive type semiconductor layer, a first electrode for supplying first power to the first conductive type semiconductor layer and a second electrode for supplying second power to the second conductive type semiconductor layer.
A great deal of research to improve electrical and optical properties of the light emitting device and the light emitting device package including the same is underway.